Improvement in enameling leather



STATES PATENT Farce.

JOHN ROSE, on NEWARK, NEW JERSEY.

IMPROVEMENT IN ENAMELING LEATHER.

In the usual mode of enameling leather a' high degree of heat is required to dry the enamel, which in consequence is liable to crack, and the leather is rendered more or less brittle. The oily matter of the leather must be extracted previous to the application of the enamel, so that the exudation of the oil under high temperature will not interfere with the drying of the enamel. By this old method of enameling large ovens are required for the drying, and the fuel for heating these ovens, as well as their construction, is found to be very expensive. The attendance upon these ovens is one of the most unhealthy employments in the arts, often producing diseases of the lungs, and not unfrequently softening of the brain.

The object of my invention is to remedy the above defects by an improvement in the art of enameling leather; and my invention orimprovement consists in the use of common salt, ammonia, and Canada balsam, in addition to other ingredients in common use in the said art, for the purpose ofmaking enameled leather of a better quality by applying the enamel at a low temperature, thus avoiding the use of ovens and the evils attendant thereupon.

In order that persons familiar with the art of enameling may understand and use my invention, I proceed to describe in detail my mode of enameling leather.

The leather should be uniformly stretched, so as to present an even surface for receiving the coating of enamel. I first applya mixture of aqua-ammonia and warm water-about one part aqua-ammonia to five parts water-rubbed on with a soft brush. I then rub the surface of the leather over with a brush dipped in the common iron liquor of tanners. When the leather is dry I next applya coating of amixture of dissolved india-rubber, lamp-black, and a little common salt. This mixture may be applied with a brush or other convenient instrument, so as to give athin coating andasmooth surface. The leather is now left about six hours to dry in a moderate temperature-say about 50 to 70 Fahrenheit. Then the coated surface of the leather is sprinkled with water slightly salted, and afterward is rubbed smooth with pumice-stone. Asecond and a third coat of this rubber mixture are applied in the same manner as the first. When the third coating is dry and rubbed smooth I apply with a camels-hair pencil a mixture of two parts Canada balsam to three parts spirits turpentine to which has been added some lamp-black or other coloring-matter. This coating also readily dries at a temperature of 50 to 70 Fahrenheit. Two coats of this mixture are usually sufficient to give a smooth surface.

The. indi'a-rubber may be dissolved in the usual manner by spirits of turpentine, about twenty-four parts of the latter, added by de grees, to one part of the former in a large vessel. Before dissolving the rubber it is common to boil it two hours in water and then cut it into shreds. I prefer then to boil it six hours in salt-water before adding the turpentine. It requires about three daysto dissolve the rubber, which I then mix with lamp-black and strain the mixture through a sieve or fine cloth before using. Although I dry my enamel at a low temperature, yet I. find that the enamel itself will bearconsiderable heat without great injury.

The advantages of my mode of preparing leather are:

First, Iproduce an articleofunusualstrength and durability, and not liable to crack.

Second, by saving the expense of ovens and fuel my mode of enameling costs from one to two dollars less than usual on each hide.

Third, the health of the workmen is not injured.

I am aware that carbonate of ammonia and sea-salt have been mixed with india-rubber, but in a manner and with results widely different from my invention. Such use of these substances I do not claim. Neither doI claim the invention of Canada-balsam varnish; but

What I do claim, and desire to secure by Letters Patent of the United States, is-

The above process of enameling leather, the whole operation being substantially as hereinabove described, and for the purposes above specified.

WM. B. GROVES, JOHN M. Fame. 

